a-model-to-simulate-clinically-relevant-hypoxia-in-humans

A Model to Simulate Clinically Relevant Hypoxia in Humans

In case of apnea, arterial partial pressure of oxygen (pO2) decreases, while partial pressure of carbon dioxide (pCO2) increases. To avoid damage to ...

a-closed-chest-model-to-induce-transverse-aortic-constriction-in-mice

A Closed-chest Model to Induce Transverse Aortic Constriction in Mice

Research on cardiac hypertrophy and heart failure is frequently based on pressure overload mouse models induced by TAC. The standard procedure is to ...

University Hospital of Bonn

University Hospital Bonn

Despite recent advances in resuscitation algorithms, neurological injury after cardiac arrest due to cerebral ischemia and reperfusion is one of the reasons for poor neurological outcome. There is currently no adequate means of measuring cerebral perfusion during cardiac arrest. It was the aim of this study to investigate the feasibility of measuring near infrared spectroscopy (NIRS) as a potential surrogate parameter for cerebral perfusion in patients with out-of-hospital resuscitations in a physician-staffed emergency medical service.

Monitoring of cerebral oxygen saturation during resuscitation in out-of-hospital cardiac arrest: a feasibility study in a physician staffed emergency medical system.

Toll-like receptor (TLR)9 ligand CpG-oligodeoxynucleotide (CpG-ODN) exerts preconditioning in myocardial ischemia/reperfusion. We hypothesized a postconditioning effect of CpG-ODN in a murine closed-chest model of myocardial infarction.

Postconditioning with a CpG containing Oligodeoxynucleotide ameliorates myocardial infarction in a murine closed-chest model.

In this study we investigated the responsiveness of near-infrared spectroscopy (NIRS) recordings measuring regional cerebral tissue oxygenation (rSO2) during hypoxia in apneic divers. The goal was to mimic dynamic hypoxia as present during cardiopulmonary resuscitation, laryngospasm, airway obstruction, or the "cannot ventilate cannot intubate" situation. Ten experienced apneic divers performed maximal breath hold maneuvers under dry conditions. SpO2 was measured by Masimo™ pulse oximetry on the forefinger of the left hand. NIRS was measured by NONIN Medical's EQUANOX™ on the forehead or above the musculus quadriceps femoris. Following apnea median cerebral rSO2 and SpO2 values decreased significantly from 71 to 54 and from 100 to 65%, respectively. As soon as cerebral rSO2 and SpO2 values decreased monotonically the correlation between normalized cerebral rSO2 and SpO2 values was highly significant (Pearson correlation coefficient = 0.893). Prior to correlation analyses, the values were normalized by dividing them by the individual means of stable pre-apneic measurements. Cerebral rSO2 measured re-saturation after termination of apnea significantly earlier (10 s, SD = 3.6 s) compared to SpO2 monitoring (21 s, SD = 4.4 s) [t(9) = 7.703, p < 0.001, r(2) = 0.868]. Our data demonstrate that NIRS monitoring reliably measures dynamic changes in cerebral tissue oxygen saturation, and identifies successful re-saturation faster than SpO2. Measuring cerebral rSO2 may prove beneficial in case of respiratory emergencies and during pulseless situations where SpO2 monitoring is impossible.

Evaluation of near-infrared spectroscopy under apnea-dependent hypoxia in humans.

Aim of this study was to investigate whether established IFCC traceable routine measurements of HbA1c levels in patients with kidney diseases result in comparable and valid results. Additionally, the influence of carbamylation as a marker of uremia on the measurement methods was assessed.

Impact of carbamylation on three different methods, HPLC, capillary electrophoresis and TINIA of measuring HbA1c levels in patients with kidney disease.

IgG subclass distribution in patients with monoclonal gammopathy.

Diving is a popular sport, and some recreational divers have medical risk factors. Their health can be endangered by high extracorporeal (ambient) pressure and its many systemic effects.

Diving medicine in clinical practice.

In Reply.

Commentaries on Viewpoint: Why predominantly neurological DCS in breath-hold divers?

Apnea diving has gained worldwide popularity, even though the pathophysiological consequences of this challenging sport on the human body are poorly investigated and understood. This study aims to assess the influence of sustained apnea in healthy volunteers on circulating microparticles (MPs) and microRNAs (miRs), which are established biomarkers reflecting vascular function.

Sustained apnea induces endothelial activation.

In acute stroke patients, thrombolysis is one gold standard therapy option within the first four hours after the ischemic event. A contraindication for thrombolysis is an International Normalized Ratio (INR) value >1.7. Since time is brain, rapid and reliable INR results are fundamental. Aim was to compare INR values determined by central laboratory (CL) analyzer and Point-of-Care Testing(POCT)-device and to evaluate the quality of POCT performance in cases of potential therapeutic thrombolysis at a certified stroke unit.

ArticleTotal : 2	Year
Publication title Cited by 1	2016
Publication title Cited by 20	2018

Article	Year
Monitoring of cerebral oxygen saturation during resuscitation in out-of-hospital cardiac arrest: a feasibility study in a physician staffed emergency medical system. Scandinavian journal of trauma, resuscitation and emergency medicine\| PubMed ID: 25286829	2014
Postconditioning with a CpG containing Oligodeoxynucleotide ameliorates myocardial infarction in a murine closed-chest model. Life sciences\| PubMed ID: 25445440	2014
Evaluation of near-infrared spectroscopy under apnea-dependent hypoxia in humans. Journal of clinical monitoring and computing\| PubMed ID: 25649718	2015
Impact of carbamylation on three different methods, HPLC, capillary electrophoresis and TINIA of measuring HbA1c levels in patients with kidney disease. Diabetes research and clinical practice\| PubMed ID: 25684605	2015
IgG subclass distribution in patients with monoclonal gammopathy. Clinica chimica acta; international journal of clinical chemistry\| PubMed ID: 25704301	2015
Diving medicine in clinical practice. Deutsches Arzteblatt international\| PubMed ID: 25797514	2015
In Reply. Deutsches Arzteblatt international\| PubMed ID: 26396052	2015
Commentaries on Viewpoint: Why predominantly neurological DCS in breath-hold divers? Journal of applied physiology (Bethesda, Md. : 1985)\| PubMed ID: 27306840	2016
Sustained apnea induces endothelial activation. Clinical cardiology\| PubMed ID: 28464406	2017
Thrombolysis in stroke patients: Comparability of point-of-care versus central laboratory international normalized ratio. PloS one\| PubMed ID: 29320558	2018

Lars Eichhorn

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